Variations in the power consumption of logic circuitry or a portion thereof may reveal details of the one or more operations performed by the logic circuitry and may reveal the data on which the one or more operations are being performed. In an example where the logic circuitry performs one or more cryptographic operations, variations in the power consumption of logic circuitry or a portion thereof may reveal any one or any combination of: cryptographic keys, random or pseudorandom numbers, details of algorithms, and data on which the one or more cryptographic operations are being performed. An attack that makes use of varying power consumption by the logic circuitry during computation is known as a power monitoring attack, which is a type of side-channel attack.
Electromagnetic (EM) probe attacks are another type of side-channel attacks. An EM probe placed over a portion of the logic circuitry will detect EM emission from that portion.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity.